The disclosed embodiments relate to a semiconductor memory device, and more particularly, to a semiconductor memory device for increasing the dynamic performance of a sense amplifier sensing data stored in a memory cell array, and a method of driving the same.
Semiconductor memory devices usually include a bit line sense amplifier (hereinafter, referred to as a sense amplifier) which receives a charge stored in a memory cell through a bit line and a complementary bit line and amplifies a voltage difference between the bit line and the complementary bit line based on the received charge to sense data stored in the memory cell. With the miniaturization of semiconductor fabrication techniques, it is important to secure an optimal sensing margin of a sense amplifier in order to decrease an operating voltage of a semiconductor memory device and reduce operating current. When an external voltage applied to the semiconductor memory device decreases according to the miniaturization of semiconductor fabrication technique and system requirements, an operating voltage of a memory core array decreases, and as a result, an input voltage of the sense amplifier diminishes due to the reduction of the voltage difference between the bit line and the complementary bit line.
A sense amplifier includes a plurality of transistors. To secure the sensing margin of the sense amplifier, the threshold voltage of the transistors included in the sense amplifier may be decreased. However, when the threshold voltages of the transistors included in the sense amplifier are decreased, sensing errors and the increase of current consumption may occur due to leakage current of the transistors.